Very interesting reading all the comments . . .
Bear in mind that MY Dipoles have always been pretty low, around 50ft. Also
that the British stations I have done proper comparisons with all have
decent verticals, typically at least 70ft high and over 40 quarter wave
radials. (you would recognis
Sorry , but all antenna's on 160m are close to the ground and it is the
case, you can check by yourself using EZENEC if you don't know how to
calculate the fields.
There is no misleading here.
73
JC
N4IS
-Original Message-
From: Topband On Behalf Of John Kaufmann
Sent: Monday, Novemb
This reminds me of the fine signals 3Y0X was producing on 160 back in
February 2006.
They were using a 3 el horisontal beam 4 ft above the ice...
73
Len SM7BIC
-Ursprungligt meddelande-
Från: Topband För Roger Kennedy
Skickat: den 27 november 2018 11:39
Till: topband@contesting.com
Ämne:
In considering the *total power* radiated by any antenna, you need to look
at the 3-dimensional antenna pattern, not a 2-dimensional slice. The total
radiated power is the 3-dimensional integration of the 3-dimensional
radiation pattern. It is convenient to do this in spherical coordinates
becaus
Yes, but according to EZNEC, a 160m dipole at 50ft produces very little
radiation at low angles, compared to one at 150ft.
But I'm sceptical about the accuracy of EZNEC with such a low antenna, as
it's just based on theory . . . I'm not convinced it can accurately model
the real-world situation
John
The issue here is not math. It is the interaction of fields and matter. A
good text book is Electromagnetic waves and radiating system by Edward C
Jordan and Keith G. Balmain. Chapter 9.
You can not ignore the close proximity with ground on 160m antennas for both
transmit signal and r
JC,
You said: " Every dipole or inverted V irradiate 50% of the power
horizontal polarized broadside with the wire and 50% of the power vertical
polarized along the wire." You cited EZNEC as evidence.
I am merely pointing out that as a general rule, this is not true. The
issue *is* math becau
Hi John
On EZNEC for sure 3D. do not use total field, under description select
horizontal and vertical field only and see the red line , vertical field and
green line horizontal field, use real ground.
Look it again.
73's
JC
-Original Message-
From: John Kaufmann
Sent: Tuesday, Nove
John
I think I understand where we disagree. Most low dipoles on 160m are 30 to
60 ft high, 1/4 wave high is not low for most stations. Very few can afford
a dipole at 120 ft high.
You right 50% is a ball parking number but it brings the attention to the
importance of 3D and separation between ho
There is no such things as "best antenna".
When I lived in Arizona, I had on a hill-top a doublet with 300 foot arms at
100 foot height (effectively more because of the hill-top). I used it both
as a doublet and as a vertical T (with the two wires of the ladder line
shorted). It had about 40 ra
Hi Paul,
Happy to! That's my problem too, lots of trees too close together.
This is the drone I ordered:
https://www.amazon.com/DROCON-Brushless-minutes-Quadcopter-Distance/dp/B06XTNS8HF/ref=as_li_ss_tl?s=toys-and-games&ie=UTF8&qid=1508031043&sr=1-4&keywords=mjx+bugs+3+BLUE&linkCode=sl1&tag=dglo
I test drove this method with a DJI Phantom and a remote release triggered
by flashing the drone's running lights. The drone had no problem carrying
1/8" nylon rope 100' into sky and releasing.
Marshall, AA0FO
On Tue, Nov 27, 2018, 2:32 PM Mike Waters Hi Paul,
>
> Happy to! That's my problem to
Hi Mike,
FB on the drone to string the line. Best of luck with it.
In case the initial 3/16 line is too heavy for the drone, I have a suggestion
that might help.
I too mostly use 3/16 line for tree antenna projects. I use an air cannon made
by a local, which has a fishing reel, and I use Daiwa b
Oooh! Thanks! I didn't think of that.
73, Mike
www.w0btu.com
On Tue, Nov 27, 2018, 2:43 PM Tree wrote:
> Trying to picture how you bring a line down from the top of a tree with a
> drone... without it getting snagged. Guess you need a weight of some kind
> to pull the rope down and away from
Interesting about the drones. I want to get one or maybe have someone who runs
them take a video of my tower and place. High quality video that is. If you
ever watch youtube/Andrew Caramata doing his property management/excavation
stuff you will be amazed by how long his video are and the distan
There are some amazing drone videos on K3LR website
Sent from my iPad
> On Nov 27, 2018, at 5:11 PM, terry burge wrote:
>
> Interesting about the drones. I want to get one or maybe have someone who
> runs them take a video of my tower and place. High quality video that is. If
> you ever watch
It's so frustrating that you always hear hundreds of stations on Top Band
whenever there's a contest on, or when there's some DX-pedition active on
the band . . . yet most of the time the band is dead !
I find it even more frustrating that there's often people posting lots
stations that are on t
The are a number of drone remote releases available. Given the small
payload capacity of cheap drones the weight is critical for everything -
line + release + sinker. The polyethylene woven fishing line has
amazing strength and low weight. I use it for my tennis ball launcher
to top 120' str
18 matches
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